Evaluate, using (a + b)(a - b)= a^2 - b^2,15.9 16.1 - Vidyadip

Question

Evaluate, using $(a + b)(a - b)= a^2 - b^2,15.9 \times 16.1$

✓

Answer

$15.9 \times 16.1$
$= (16 - 0.1) \times (16 + 0.1)$
$= (16)^2 - (0.1)^2$
$= 256 - 0.01$
$= 255.99.$

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